Abstract

Vehicular Ad Hoc Networks (VANETs) are envisaged to be a critical building block of Smart Cities and Intelligent Transportation System (ITS) where pollution and congestion reduction, vehicle mobility improving, accidents prevention, safer roads are some of VANETs expected benefits. The vehicular communications encompass three major approaches: Vehicle-to-Vehicle (V2V), Vehicle-to-Infrastructure (V2I) and Vehicle-to-Pedestrian (V2P). Although there is a significant research effort in VANETs radio channel characterization, the use of more general methods than theoretical and empirical models is required to understand more accurately the propagation phenomena in urban environments. In this work, a deterministic computational tool based on an in-house 3D Ray-Launching algorithm and standard IEEE 802.11p, are used to measure and represent the spatial large-scale and small-scale urban radio propagation phenomena for V2I and V2P communications. Spatial analysis of the path loss (PL), Power Delay Profile (PDP), Coherence Bandwidth (CB), Doppler shift, Doppler spread along avenues is presented in order to characterize the impact that the obstacles (geometry, electromagnetic properties and relative position), distance, link frequency, placement of Road Side Units (RSUs) and location of wearable sensors, have in the V2I and V2P propagation channels. Results show the impact of the temporal and spatial variation in the received signal power, due to the time dispersive behavior and rapid changes between Line-of-sight (LoS), Quasi-line-of-sight (QLoS) and Non-line-of-sight (NLoS) of the urban environments. These results should be useful for radio-planning Wireless Sensor Networks (WSNs) designers in future V2V and V2P communication systems.